<template>
	<u-popup v-model="show" mode="bottom" length="80%">
		<view class="u-wrap">
			<view class="search-box">
				<u-search placeholder="搜索更多话题" v-model="keyword" :action-text="actionText" @custom="close"></u-search>
			</view>
			<view>
				<view class="page-select" v-if="tagList.length > 0">
					<view class="select-item">
						<view class="item-title">
							<text>已选话题</text>
						</view>
						<view class="item-container">
							<view class="select-thumb-box" v-for="(item, index) in tagList" :key="index">
								<u-image width="220" height="120" :src="item.image"></u-image>
								<view class="item-menu-name">#{{item.title}}#</view>
								<view class="close" @click="removeTag(item)">
									<u-icon name="guanbi1" custom-prefix="iconfont"></u-icon>
								</view>
							</view>
						</view>
					</view>
				</view>
			</view>
			<view class="u-menu-wrap">
				<scroll-view scroll-y scroll-with-animation class="u-tab-view menu-scroll-view" :scroll-top="scrollTop">
					<view v-for="(item,index) in tabbar" :key="index" class="u-tab-item" :class="[current==index ? 'u-tab-item-active' : '']"
					 :data-current="index" @tap.stop="swichMenu(index)">
						<text class="u-line-1">{{item.name}}</text>
					</view>
				</scroll-view>
				
				<scroll-view scroll-y class="right-box" v-if="current==0">
					<view class="page-view">
						<view class="class-item">
							<view class="item-title">
								<text>{{tabbar[current].name}}</text>
							</view>
							<view class="item-container">
								<view class="thumb-box" v-for="(item, index) in topicList" :key="index">
									<u-image @click="selectTag(item)" width="240" height="120" :src="item.image"></u-image>
									<view class="item-menu-name">#{{item.title}}#</view>
								</view>
							</view>
						</view>
					</view>
				</scroll-view>
				
				<scroll-view scroll-y class="right-box" v-if="current==1">
					<view class="page-view">
						<view class="class-item">
							<view class="item-title">
								<text>{{tabbar[current].name}}</text>
							</view>
							<view class="item-container">
								<view class="thumb-box" v-for="(item, index) in fansTopicList" :key="index">
									<u-image @click="selectTag(item)" width="240" height="120" :src="item.image"></u-image>
									<view class="item-menu-name">#{{item.title}}#</view>
								</view>
							</view>
						</view>
					</view>
				</scroll-view>
			</view>
		</view>
		<u-toast ref="uToast" />
	</u-popup>
</template>

<script>
	import classifyData from "@/common/classify.data.js";
	export default {
		props: {
			topicList: {
				// 动态数据
				type: Array,
				required: true,
				default: function() {
					return [];
				}
			},
			fansTopicList: {
				// 动态数据
				type: Array,
				required: true,
				default: function() {
					return [];
				}
			},
		},
		data() {
			return {
				keyword: '',
				tagList: [],
				actionText: '取消',
				tabbar: classifyData,
				scrollTop: 0, //tab标题的滚动条位置
				current: 0, // 预设当前项的值
				menuHeight: 0, // 左边菜单的高度
				menuItemHeight: 0, // 左边菜单item的高度
				show: false,
			}
		},
		computed: {
			
		},
		methods: {
			getImg() {
				return Math.floor(Math.random() * 35);
			},
			// 点击左边的栏目切换
			async swichMenu(index) {
				if(index == this.current) return ;
				this.current = index;
				// 如果为0，意味着尚未初始化
				if(this.menuHeight == 0 || this.menuItemHeight == 0) {
					await this.getElRect('menu-scroll-view', 'menuHeight');
					await this.getElRect('u-tab-item', 'menuItemHeight');
				}
				// 将菜单菜单活动item垂直居中
				this.scrollTop = index * this.menuItemHeight + this.menuItemHeight / 2 - this.menuHeight / 2;
			},
			// 获取一个目标元素的高度
			getElRect(elClass, dataVal) {
				new Promise((resolve, reject) => {
					const query = uni.createSelectorQuery().in(this);
					query.select('.' + elClass).fields({size: true},res => {
						// 如果节点尚未生成，res值为null，循环调用执行
						if(!res) {
							setTimeout(() => {
								this.getElRect(elClass);
							}, 10);
							return ;
						}
						this[dataVal] = res.height;
					}).exec();
				})
			},
			open() {
				this.tagList = [];
				this.show = true;
			},
			close() {
				this.show = false;
				if(this.tagList.length > 0){
					this.$emit('tagOk', this.tagList);
				}
			},
			removeTag(tag) {
				var index = this.tagList.indexOf(tag);
				this.tagList.splice(index, 1);
				if(this.tagList.length < 1){
					this.actionText = '取消';
				}
			},
			selectTag(tag) {
				if(this.tagList.length < 3){
					var flag = this.checkTag(tag.id);
					if(!flag){
						this.tagList = [];
						this.tagList.push(tag);
					}
				}else{
					this.$refs.uToast.show({title: '最多选择3个话题',type: 'warning'});
				}
				if(this.tagList.length > 0){
					this.actionText = '完成';
				}
			},
			checkTag(id) {
				for(var i=0;i<this.tagList.length;i++){
					var tag = this.tagList[i];
					if(tag.id == id){
						return true;
					}
				}
				return false;
			},
		}
	}
</script>

<style lang="scss" scoped>
	.u-wrap {
		height: calc(100vh);
		/* #ifdef H5 */
		height: calc(100vh - var(--window-top));
		/* #endif */
		display: flex;
		flex-direction: column;
	}

	.u-search-box {
		padding: 18rpx 30rpx;
	}

	.u-menu-wrap {
		flex: 1;
		display: flex;
		overflow: hidden;
	}

	.u-search-inner {
		background-color: rgb(234, 234, 234);
		border-radius: 100rpx;
		display: flex;
		align-items: center;
		padding: 10rpx 16rpx;
	}

	.u-search-text {
		font-size: 26rpx;
		color: $u-tips-color;
		margin-left: 10rpx;
	}

	.u-tab-view {
		width: 200rpx;
		height: 100%;
	}

	.u-tab-item {
		height: 110rpx;
		background: #f6f6f6;
		box-sizing: border-box;
		display: flex;
		align-items: center;
		justify-content: center;
		font-size: 26rpx;
		color: #444;
		font-weight: 400;
		line-height: 1;
	}
	
	.u-tab-item-active {
		position: relative;
		color: #000;
		font-size: 30rpx;
		font-weight: 600;
		background: #fff;
	}
	
	.u-tab-item-active::before {
		content: "";
		position: absolute;
		border-left: 4px solid $u-type-primary;
		height: 32rpx;
		left: 0;
		top: 39rpx;
	}

	.u-tab-view {
		height: 100%;
	}
	
	.right-box {
		background-color: rgb(250, 250, 250);
	}
	
	.page-view {
		padding: 16rpx;
	}
	
	.page-select {
		padding: 0 10rpx;
	}
	
	.class-item {
		margin-bottom: 30rpx;
		background-color: #fff;
		padding: 16rpx;
		border-radius: 8rpx;
	}
	
	.select-item {
		margin-bottom: 10rpx;
		background-color: #fff;
		padding: 16rpx;
		border-radius: 8rpx;
	}
	
	.item-title {
		font-size: 26rpx;
		color: $u-main-color;
		font-weight: bold;
	}
	
	.item-menu-name {
		font-weight: normal;
		font-size: 24rpx;
		color: $u-main-color;
	}
	
	.item-container {
		display: flex;
		flex-wrap: wrap;
	}
	
	.thumb-box {
		width: 50%;
		display: flex;
		align-items: center;
		justify-content: center;
		flex-direction: column;
		margin-top: 20rpx;
	}
	
	.select-thumb-box {
		width: 33.333333%;
		display: flex;
		align-items: center;
		justify-content: center;
		flex-direction: column;
		margin-top: 20rpx;
		position: relative;
	}
	
	.item-menu-image {
		width: 120rpx;
		height: 120rpx;
	}
	
	.search-box {
		padding: 10px;
	}
	
	.close {
		position: absolute;
		top: 3px;
		right: 5px;
		color: #f2f2f2;
	}
</style>
